John Sparks, associate curator and curator-in-charge, department of Ichthyology at the American Museum of Natural History, and David Gruber, assistant professor at the City University of New York and a research associate at the museum, discuss the variety of bioluminescent organisms—from fungus to dinoflagellates to jellyfish—and explain the various ways they glow, the functions of bioluminescence, and how scientists study it. The exhibition Creatures of Light: Nature’s Bioluminescence is on view at the American Museum of Natural History through January 6, 2013.